Fix image update mutation to ignore alt if it wasn't provided
Fix image update mutation to ignore alt if it wasn't provided

mociepka/saleor,UITools/saleor,UITools/saleor,maferelo/saleor,UITools/saleor,UITools/saleor,maferelo/saleor,mociepka/saleor,mociepka/saleor,UITools/saleor,maferelo/saleor